force-closing persistent server connections

[carglue]

Within an extension, is there any other way to close out persistent
(keep-alive) http network connections other than sending the following
two notifications?

profile-change-net-teardown
profile-change-net-restore

Unfortunately, doing it this way also close my own tcp connection that I
use for external communication. I've tried to simply update some of the
prefs, but they do not apear to force-close persistent http connections
without a full browser restart.

Thx